/* Copyright 2015 The TensorFlow Authors. All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/

#ifndef TENSORFLOW_KERNELS_SCATTER_OP_H_
#define TENSORFLOW_KERNELS_SCATTER_OP_H_

// Functor definitions for Scatter ops, must be compilable by nvcc.

#include "third_party/eigen3/unsupported/Eigen/CXX11/Tensor"
#include "tensorflow/core/framework/tensor_types.h"

namespace tensorflow {

class OpKernelContext;

namespace scatter_op {

enum class UpdateOp { ASSIGN, ADD, SUB };

}  // namespace scatter_op

namespace functor {

// Functor used by ScatterOp to do the computations.
template <typename Device, typename T, typename Index, scatter_op::UpdateOp op>
struct ScatterFunctor {
  // Returns -1 on success or a nonnegative i s.t. indices[i] is a bad index.
  Index operator()(OpKernelContext* c, const Device& d,
                   typename TTypes<T>::Matrix params,
                   typename TTypes<T>::ConstMatrix updates,
                   typename TTypes<Index>::ConstFlat indices);
};

}  // namespace functor
}  // namespace tensorflow

#endif  // TENSORFLOW_KERNELS_SCATTER_OP_H_
